General hints:
I never had a mirror on the extreme left or extreme right side. Sometimes you have to circle way around the deep water to push mirrors into the correct spot. You've probably noticed this already, but counting the mirrors reveals that you need to make vertical progress with all mirrors except for three of them. The room doesn't really give you much feedback as to if you've already wasted too many mirrors, but try to get at least 5 rows down before pushing one in a way that doesn't make direct vertical progress.
Full spoiler:
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×There's probably more than one possible way to do this (one would hope at least), but the setup below should do it.
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Links to neat forum tools that I always have trouble finding:
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